first commit

build/node_modules/base62/base62.js

@@ -0,0 +1,76 @@
+module.exports = (function (Base62) {
+    "use strict";
+
+    var DEFAULT_CHARACTER_SET = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";
+
+    Base62.encode = function(integer){
+        if (integer === 0) {return '0';}
+        var s = '';
+        while (integer > 0) {
+            s = Base62.characterSet[integer % 62] + s;
+            integer = Math.floor(integer/62);
+        }
+        return s;
+    };
+
+    var defaultCharsetDecode = function defaultCharsetDecode (base62String) {
+        var value = 0,
+            i = 0,
+            length = base62String.length,
+            charValue;
+
+        for (; i < length; i++) {
+            charValue = base62String.charCodeAt(i);
+
+            if (charValue < 58) {
+                charValue = charValue - 48;
+            } else if (charValue < 91) {
+                charValue = charValue - 29;
+            } else {
+                charValue = charValue - 87;
+            }
+
+            value += charValue * Math.pow(62, length - i - 1);
+        }
+
+        return value;
+    };
+
+    var customCharsetDecode = function customCharsetDecode (base62String) {
+        var val = 0,
+            i = 0,
+            length = base62String.length,
+            characterSet = Base62.characterSet;
+
+        for (; i < length; i++) {
+            val += characterSet.indexOf(base62String[i]) * Math.pow(62, length - i - 1);
+        }
+
+        return val;
+    };
+
+    var decodeImplementation = null;
+
+    Base62.decode = function(base62String){
+        return decodeImplementation(base62String);
+    };
+
+    Base62.setCharacterSet = function(chars) {
+        var arrayOfChars = chars.split(""), uniqueCharacters = [];
+
+        if(arrayOfChars.length !== 62) throw Error("You must supply 62 characters");
+
+        arrayOfChars.forEach(function(char){
+            if(!~uniqueCharacters.indexOf(char)) uniqueCharacters.push(char);
+        });
+
+        if(uniqueCharacters.length !== 62) throw Error("You must use unique characters.");
+
+        Base62.characterSet = arrayOfChars;
+
+        decodeImplementation = chars === DEFAULT_CHARACTER_SET ? defaultCharsetDecode : customCharsetDecode;
+    };
+
+    Base62.setCharacterSet(DEFAULT_CHARACTER_SET);
+    return Base62;
+}({}));